Noninvasive Ventilation Using a Mouthpiece in Patients with Chronic Obstructive Pulmonary Disease and Acute Respiratory Failure.

Background: Noninvasive positive pressure ventilation (NPPV) delivered via a mouthpiece (mNPPV) has been successfully used in stable chronic restrictive respiratory insufficiency, but not in patients with chronic obstructive pulmonary disease (COPD) and acute respiratory failure (ARF). Objectives: The purpose of this matched case-control study was to compare the usefulness of mNPPV to noninvasive ventilation using a nasal or oronasal mask (nNPPV) or standard medical treatment (SMT) in COPD patients with ARF. Methods: Twenty-nine patients receiving mNPPV were matched with 29 patients receiving nNPPV and 29 patients receiving SMT regarding age, SAPSII, admission PaCO₂ and pH. Results: In the mNPPV group, admission PaCO₂ and pH were 78.6 ± 12 mm Hg and 7.30 ± 0.04, respectively. mNPPV and nNPPV avoided the need for endotracheal intubation in 27 and 25 patients, respectively (nonsignificant) whereas SMT resulted in a higher mechanical ventilation rate (13 patients). At the end of the treatment protocol, PaCO₂ was lower in the mNPPV group (62.2 ± 9.6 mm Hg) than in the SMT group (72.4 ± 20.4 mm Hg, p < 0.018) leading to a significantly higher pH. No significant differences were observed between the mNPPV and nNPPV groups. Conclusions: In case of moderate respiratory acidosis, noninvasive ventilation using a mouthpiece significantly reduces the endotracheal intubation rate in comparison with SMT and therefore appears to be a second-line alternative to noninvasive ventilation delivered via a mask, especially when poorly tolerated. Copyright © 2007 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]